This invention relates in general to apparatuses for mounting auxiliary wheels on bicycles, such as those generally used for training purposes. In particular, this invention relates to longitudinally resilient axles for mounting auxiliary wheels on opposite sides of a bicycle wheel for lateral stability.
For some background, training wheels are those wheels attached to the rear axle of a bicycle to provide it with vertical stability. They are especially used to help small children learn how to ride bicycles. Conventional rigid auxiliary axles extend laterally from the back wheel, usually attached to the rear wheel axle by some bracket means, with small wheels are mounted thereon. These wheels are typically not flush with the bottom of the bicycle's rear wheel so that when the bicycle is moving, it is riding on its normal two wheels. The side wheels only come into play when the bicycle is laterally tilted.
The proper way to turn a bicycle is to lean into the turn rather than twist the front wheel in a new direction. In order for conventional, rigid axle training wheels to allow for leaning into turns, the bottom of the wheels must be spaced above the bottom of the bicycle's rear wheel. This, however causes another problem because if the child leans too far and the bicycle comes to rest on one of the training wheels, the child may not have enough weight and/or strength to right the bicycle and will thereafter be locked into a continuous turn.
Others have devised complicated solutions to this problem.
U.S. Pat. No. 2,450,979 by Moller describes a set of training wheels on axles that are spring loaded and that can rotate vertically within a limited range. The training wheels are shown to be flush with the bottom of the back wheel and Moller describes the invention as permitting the natural tendency of a rider to lean or bank inwardly when making a turn. The spring loading is accomplished by coiled springs at what appears to be a 45.degree. angle and the axles are attached to the back wheel axle by L-shaped brackets.
U.S. Pat. No. 4,133,402 by Soo Hoo describes a pair of training wheels or stabilizing wheels for motorcycles. The side wheels are attached by pairs of strut rods in a pivotal arrangement so that as the back wheel tilts, the inside stabilizing wheel tilts at the same angle to avoid skidding.
U.S. Pat. No. 2,793,877 by Meier, Jr. describes another set of training wheels attached to the back wheel axle by L-shaped brackets. The axles of the training wheels are each attached to a flat or leaf spring that is bent in generally an L-shape, however the memory of the springs tends to straighten them out. Thus, as a rider banks into a turn, the inside axle rotates upward to a limit and the outside axle due to the spring's memory rotates downward keeping it in contact with the ground.
U.S. Pat. No. 4,203,500 by Kamiya describes a motorcycle with wings extending from opposite sides having raised wheels at the wing tips. They are not really wings but rather pivotally attached strut pairs. As a motor cycle banks into a turn, the wheels come into contact with the ground and assume an angle counter to the angle to the motorcycle to prevent the motorcycle from turning over.
U.S. Pat. No. 4,595,213 by Tsuchie describes another pair of training wheels for bicycles attached by generally L-shaped brackets. The wheel axles are vertically rotatable and spring biased by vertical coil springs. FIG. 4 illustrates their action when the bicycle banks into a turn. This is very similar to the Moller patent except that the coil springs are vertical rather than angled.
U.S. Pat. No. 4,810,000 by Saunders describes another pair of bicycle training wheels basically supported by brackets attached to the rear axle of the bicycle. In this case, the wheels are pivotally connected by respective arms to rotate in a plane parallel to the plane of the rear wheel. The pivoting of the training wheels is controlled by respective cables attached to the front wheel fork. When the front wheel is pointed straight ahead, the training wheels are flushed with the bottom of the bicycle rear wheel, however if the front wheel is turned to the right or the left the mechanical motion of the turn is communicated to the pivot arms of the training wheels via the cable causing the inside wheel to pivot upward and the outside wheel to pivot downward thereby keeping both in contact with the ground.
U.S. Pat. No. 5,064,213 by Storch describes another pair of training wheels for bicycles. These are again attached to the rear axle by generally an L-shaped bracket and they are flush with the bottom of the rear wheel. They are also spring biased by coil springs at an angle. It appears that in the normal upright position, the coil springs are somewhat compressed so that when the bicycle leans into a turn, the inside spring is compressed further by upward rotation of the inside wheel axle and the outside spring expands causing the downward rotation of the outside wheel's axle keeping both in ground contact.
U.S. Pat. No. 5,100,163 by Egley et al. describes another pair of training wheels very similar to Storch with the addition of a means for adjusting the tension on the coil springs and a limiter which sets the limit that the axles can rotate upward. FIG. 3 shows this limiter to be adjustable.
These prior art references all disclose very complicated and costly devices to overcome the drawbacks of rigid auxiliary axles, whereas this invention presents a simple yet most effective way to accomplish the same end.
Other advantages and attributes of this invention will be readily discernable upon a reading of the text hereinafter.